The Holliday-Segar Method

In the Holliday-Segar Method,
fluid and electrolyte requirements are empirically based on the caloric
needs of the average hospital patient. This caloric expenditure is
approximated based on body weight using the following table:

Relation of Body Weight to Caloric Expenditure

For each kilogram in this range

Daily caloric cost per kilogram

1-10 kg

100 kcal/kg/day

11-20 kg

50 kcal/kg/day

>20 kg

20 kcal/kg/day

For every 100 kcal expended, a certain amount of fluid is lost either
through "insensible water loss" or through renal function; a small amount
is generated through oxidation of carbohydrates and tissue catabolism.
Also, for every 100 kcal expended, electrolytes are lost in the following
proportions:

Maintenance Electrolyte Requirements

Na

3 mEq per 100 kcal/day

K

2 mEq per 100 kcal/day

Cl

2 mEq per 100 kcal/day

Example: Calculate the daily fluid requirements of a 10 year old
boy who weighs 32 kg using the Holiday-Segar method:

Kcal expended

10*100 + 10*50 + 12*20

1740 kcal

H20 required

1740 kcal * 100 cc/100 kcal

1740 mL H2O

Na required

1740 kcal * 3 mEq/100 kcal

52.2 mEq Na

K required

1740 kcal * 2 mEq/100 kcal

34.8 mEq K

Cl required

1740 kcal * 2 mEq/100kcal

34.8 mEq Cl

Given good renal function and no overriding concerns about excess sodium,
a maintenance fluid to provide at least the required amount of sodium.
Potassium is usually added after the patient's first void in an amount
that will yield the above maintenance level. Chloride is usually
not a concern in and of itself, but is a passive ion. A table of
common solutions can be consulted to pick an appropriate solution.

In this case, the target solution should have 52.2 mEq Na per 1.74 liters,
or 30 mEq Na per liter. The closest solution is the 34.2 mEq/L found
in 0.2% saline. Each liter should also contain 20 mEq of potassium.

The Holiday-Segar can be used to quickly estimate fluid requirements
in terms of mL/hour (a useful way of expressing it, since this is how IV
infusion pumps are programmed):

Notes:
1. The Holiday-Segar method can only be applied to patients above
2 weeks of age.
2. This method does not take into consideration caloric expenditures
above average, or take into account on-going fluid losses; a more rigorous
method would be the caloric method.